NUCLEON DESCRIPTION IN A PROJECTED CHIRAL SOLITON MODEL WITH DYNAMICAL CONFINEMENT

We present a nucleon description based on a chiral version of a colour -dielectric model with non-strange quarks and scalar-isoscalar (sigma) and pseudoscalar-isovector (pi over arrow pointing right) meson field s. Approximate solutions of the model are obtained in a beyond-mean-fi eld calculation. Quarks are treated in the valence approximation, occu pying the same nodeless s-orbit. Coherent states are used to describe the meson clouds. The total baryon state has a hedgehog shape. A stand ard projection formalism is used to obtain model states with definite angular momentum and isospin and total linear momentum zero. To a larg e extent we use a variation-after-projection (VAP) procedure to obtain radial amplitudes for the mesons and quarks. The model state which de scribes the nucleon is used for evaluating its static properties. The projection on linear momentum causes a major effect on the rest mass o f the nucleon. This effect amounts to approximately 30% decrease with respect to the mean-field energy. Except for the charge radius of the proton, the other observables are less affected by the projections. We find sets of parameters for which a reasonable nucleon description is obtained.